Liquid crystal display (LCD) devices have become popular in recent years. These display devices typically offer the advantage of being thinner and lighter than conventional cathode ray tube (CRT) displays. Moreover, LCD devices typically require less power than CRT displays.
In its simplest form, an LCD device includes a liquid crystal material interposed two glass panels and two polarizing filters. Typically, an external light source directs light onto the LCD. For example, in most computers employing an LCD, fluorescent tubes and diffusion panels scatter light onto the LCD. The light typically is directed through to the liquid crystal material, which depending on its state, may either allow light to pass through the display or diffuse the light. The state of the liquid crystal material typically is controlled via an electrode or switching device.
Specifically, the polarizing filters in an LCD may operate to pass only light that is oriented in a specific direction. These filters may significantly reduce the amount of light that is produced by the display. Such a reduction may substantially reduce the overall brightness of the display.
Color LCD devices also may suffer from a loss of light. For example, in a typical color LCD device, each display pixel includes three separate sub-pixels, a red sub-pixel, a green sub-pixel, and a blue sub-pixel. Each sub-pixel typically includes a color filter that allows light of a certain wavelength to pass through. Thus, the maximum transmission of any primary color in an LCD array may only be through one-third of the pixels. Moreover, the perception of white light may be a result of each filter simultaneously allowing red, green, and blue light to pass. Filtering out unwanted wavelengths results in a reduction in the brightness of the display. To compensate for the reduction in brightness, a high-powered backlight may be employed. However, such a light may cause an increase in the temperature, weight, bulk, power consumption, and cost of the system.
The sub-pixels in a color LCD may further impact the resolution of the display. As briefly described above, a color LCD device typically includes an array of pixels. Each pixel may include sub-pixels, which are typically arranged in a common plane. Regardless of the arrangement, each such sub-pixel requires a certain amount of physical space. This physical space requirement affects how tightly the pixels may be packed together in the LCD array. Thus, both the resolution and the brightness of the screen may be constrained by the physical arrangement and size of the sub-pixels.